JPH02214663A - Recording head - Google Patents

Abstract

PURPOSE:To enable higher integration through micro-fabrication by generating a deformation in a base part of a partition wall to cause a displacement of the wall, thereby changing the volume of an ink passage to jet an ink droplet outward through a nozzle. CONSTITUTION:With a voltage applied to an electrode 7-1, a piezoelectric vibrator 3 is changed in shape under the effect of an electric field. For instance, the vibrator 3 is displaced in the thickness direction thereof, whereby a partition wall 4-1 is displaced from the solid-line position to the broken-line position. In this case, application of a voltage to an electrode 72 (opposite to the electrode 7-1 in polarity) promotes the displacement of the partition wall 4-1. The displacement of the wall 4-1 causes a pressure change in a passage 6-2, whereby an ink droplet is ejected through a nozzle 2. The ejecting operation can also be achieved by a draw striking method, in which the above operation is carried out comparatively slowly, followed by cutting off the voltage, upon which the wall 4-1, tends to return to the initial position thereof, with the result of a pressure change in a passage 6-1, whereby the ink is ejected through a nozzle 2 communicating with the passage 6-1. In this construction, the partition walls defining the passages can be formed from an arbitrary material, so that the technique for forming fine grooves in fabrication of semiconductor devices can be utilized, which is advantageous to higher integration.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording head for a printer, and more particularly to a recording head for a printer used in a copying machine or a facsimile machine.

9 and 10 are block diagrams of a conventional pressurizing on-demand multi-head, with FIG. 9 showing a sectional view and FIG. 10 showing a top view thereof. In the figure, 21 is an upper plate, 22 is an electrostrictive vibrator, 23 is an ink supply 1 supply path, 24 is an ink supply side flow path, 25 is an ink pressurizing liquid chamber, 26 is a substrate, 27 is a flow path,
28 is a nozzle.

29 is a common liquid chamber, and 30 is an ink supply hole. This pressurized on-demand multi-head uses an electrostrictive vibrator to pressurize the liquid chamber and eject ink from the nozzle.If the vibrator has a small area, the ink ejection energy cannot be secured.
Increasing the area of the vibrator makes the head bulky, which limits high integration. Currently, it is best to accumulate several dozen nozzles.

In addition, FIG. 11 shows the prior art in Japanese Patent Application Laid-open No. 63-2527.
One of the drawings described in Publication No. 50.

3.1 is a nozzle, 32 is a piezoelectric element (PZT), and 33 is an ink flow path. The above publication relates to a high-density multi-channel array pulse droplet deposition device and a method for manufacturing the device. Ink is ejected from the nozzle due to the pressure change when it returns to its original position.

Furthermore, since PZT (piezoelectric vibrator) is used as a component of the flow path, there are limits to the processing method. That is, the most common method is to process the grooves with a dicing saw. This requires considerable processing cost, and
Because ZT itself is extremely brittle, the processed corners (
Edges) may be chipped, making it impossible to form a uniform flow path, leading to image deterioration.

Furthermore, forming the electrode and drawing it out is quite difficult;
Even if it were possible, the process would be complicated and it would be disadvantageous in terms of cost.

Furthermore, since the electrodes and PZT come into direct contact with the ink, there are problems such as the need for protection such as a protective film.

■---Five inventions were made in view of the above-mentioned circumstances.
This was done for the purpose of providing a recording head that achieves high integration through microfabrication.

In order to achieve the above object, the present invention provides a nozzle or orifice, an ink passage communicating with the nozzle, a partition wall separating the ink passage individually, and an ink supply section communicating with the ink passage. A deformation generating member is provided for generating deformation at the root portion of the partition wall, and when the deformation generating member is driven, deformation is generated at the root portion of the partition wall to cause displacement of the partition wall, thereby creating a volume in the ink passage. The ink droplet is ejected from the nozzle by causing a change in the ink droplet. Hereinafter, the present invention will be explained based on examples.

1 to 3 are configuration diagrams for explaining one embodiment of the recording head according to the present invention. FIG. 1 is a partial sectional view of the recording head, and FIG. 2 is a partial cross-sectional view of the recording head, and FIG. Figure,
FIG. 3 is a front view. In the figure, 1 is a nozzle plate, 2
3 is a nozzle, 3 is a piezoelectric vibrator, 4 is a substrate, 4. 4 and 2 are bulkheads, and 5 is a top plate.

6, ~6. ．． 71 and 7.2 are electrodes, and 8 is a fixing plate. The substrate 4 is made of silicon oxide (S i O,), and the grooves forming the flow channels 6 are formed by etching technology. The flow path 6 is partitioned by partition walls 4, 4, 4, 8, . The substrate 4 has partition walls 4. i, 41. , . . . A piezoelectric vibrator 3 polarized in accordance with each flow path pitch is fixed to the opposite surface.

A nozzle plate l having minute holes (for example, 30 μ to 50 μ) is fixed to one end of the flow path. This nozzle (or orifice) is connected to each flow path 6, . 6. ,,...
・Compatible with The recording head unit 12 is attached to the fixed plate 8
be fixed and placed. or.

Separate members that make up the flow path and members that drive it make the most of the characteristics of each (if the flow path is made of PZT, there are problems with groove processing methods, pitch, mass production, etc.) ), but as shown in FIG. 4, an electrode may be disposed at the base of the partition wall made of PZT.

Further, as shown in FIG. 5, a notch may be made in the bottom of the substrate so that it can be easily displaced when the PZT is driven.

FIG. 6 is a diagram for explaining the operation of the recording head according to the present invention. When a voltage is applied to the electrode 7□, the piezoelectric vibrator 3 changes its shape under the influence of the electric field.
In the figure, when a voltage is applied to 7.1, displacement occurs in the thickness direction, and the partition wall 4.1 is displaced from the solid line to the broken line. At this time, apply voltage to electrode 7.2 (opposite polarity to 7, □)
This facilitates the displacement of the partition wall 41. Due to this displacement of the partition wall 4-□, the flow path 6. , a pressure change occurs, and an ink droplet is ejected from the nozzle 2. -Also, conversely, -a method called the ``pulling method'' for fishing on a boat also suppresses the discharging operation. Namely.

Perform the above operation relatively slowly, and then cut off the voltage. Then, the partition wall 41 tries to return to its original state, and the flow path 6
A pressure change is generated within the nozzle 2, and ink is ejected from the nozzle 2 communicating with the nozzle 2.

FIG. 7 is a diagram showing an example of using the recording head according to the present invention, in which 9 is an ink supply tank, 10 is a recording paper,
11 is an ink supply chamber, and 12 is a recording head unit.

FIG. 8 is a diagram showing another embodiment of the present invention. In the figure, 7 is a common electrode, 13 is a protective layer, and other parts having the same function as the head shown in FIG. , with the same reference numerals as in FIG. According to this, a protective layer 13 (for example, 5i02, etc.) is provided in place of the substrate 4, partition walls 11, 4, 2, etc. are arranged (for example, by dry film, etc.), and one of the electrodes is a common electrode. (In the figure, the common electrode is on the flow path side.) Further, the piezoelectric vibrator 3 may be polarized over the entire surface of the vibrator, and the partition walls 4
．． ,． 4. , . . . and the upper plate 5 do not need to be connected to each other as long as there is sufficient fluid resistance. That is, the channels 6-□ and 64 do not need to be completely separated.

As is clear from the above description, according to the present invention, the partition walls constituting the flow path can be made of any material. Therefore, groove processing technology based on semiconductor processing related technology, which is best suited for fine processing, can be used, which is advantageous for high integration.

[Brief explanation of the drawing]

1 to 3 are configuration diagrams for explaining one embodiment of a recording head according to the present invention, in which FIG. 1 is a partial sectional view, and FIG.
The figure is a view of Figure 1 with the nozzle plate removed, Figure 3 is a front view, Figure 4 is a diagram showing another embodiment of the electrode arrangement, and Figure 5 is a diagram showing another embodiment of the bottom of the substrate. 6 are diagrams for explaining the operation of the recording head according to the present invention, FIG. 7 is a diagram showing an example in which the recording head according to the present invention is used, and FIG.
The figure shows another embodiment of the present invention, and FIGS. 9 to 11 are diagrams for explaining a conventional example. DESCRIPTION OF SYMBOLS 1... Nozzle plate, 2... Nozzle, 3... Piezoelectric vibrator, 4... Substrate, i, 4. ... bulkhead,
5...Top plate, 6-1 to 61. ...Flow path, 7-1.
7. ,...electrode, 8...fixing plate. Figure 1 Figure 3 Figure 4

Claims (1)

[Claims] 1. It has a nozzle or orifice, an ink passage that communicates with the nozzle, a partition that partitions the ink passage individually, and an ink supply section that communicates with the ink passage, and causes deformation in the base of the partition. A deformation generating member is provided, and by driving the deformation generating member, a deformation is generated at the base of the partition wall to cause displacement of the partition wall, a volume change is generated in the ink passage, and an ink droplet is ejected from the nozzle. Features a recording head.